1. Field of the Invention
The invention is related to the field of communications, and in particular, to the use of shared protect links for the back-up operations of multiple communication services.
2. Description of the Prior Art
Internet Protocol (IP) communications systems frequently use IP routers that are set-up as matched pairs. If one of the IP routers in the pair fails, then the other IP router in the pair can take over for the failed IP router. In addition, IP routers are connected over two diverse links. If one of the links between two IP routers fails, then the IP routers use the other link.
Since the IP routers and their links must back each other up, they must retain significant excess capacity to perform their back-up role. Unfortunately, this form of back-up protection requires a serious overbuild in IP links and routers. The overbuild results a excess cost and complexity.